deleting 2/3 blogs

I want to delete two of my three blogs within my account but keep the one I have been using. I made technical mistakes on the other two when I was learning and want them deleted. When I have attempted to use the delete blog option on the site it says ALL of my material will be deleted and I will never be able to get my username/site back. How do I just permanently delete the ones I do not want?
Thank you.